Long Multiplication sums (tu x tu) - Step by Step Explanation - Quick Method
Learning to multiply a 2 digit number by another 2 digit number can appear to be quite daunting. But once you understand the technique, you can easily mulitply 2 or 3 digit numbers, using the column method, easily and quickly. There are many ways you can multiply larger numbers together e.g grid method, expanded column method, column method etc. Watch this video showing How to do a long multiplication sum using the column method.
Some children will find one method easier to understand and use. Children can be shown the different methods of multipliying numbers, this may help when they are first learning the principles behind long multiplication sums. Once they are more confident, they can then move onto the quick, efficient way of long multiplication sums. This will help them in tests and exams, where the time taken to work out a sum matters. Schools may teach how to solve long multiplication sums in a variety of ways.
Long Multiplication Sums Explained Step by Step (Column Method)
Below is an example of how to work out a long multiplication sum using the quick, efficient column method.
Multiplication Sum: 43 x 12 =
- Write th numbers into columns. Remember to put the tens and units for each number underneath each other.
x 1 2
- First multiply 43 x 2
x 1 2 (2 x 3 = 6) then (2 x 4 = 8) Write the answers to these sums underneath, as you would in an addition sum.
There are no numbers to carry over, if there are numbers to carry over, this can be done in the same way you would with an addition sum.
- Next multiply 43 x 10
Although we are going to multiply 43 x 10, we will first place a 0 underneath the 6. We do this because we know that whenever a number is multiplied by 10 the answer ends in a 0.
We can then continue with the sum.
x 1 2
4 3 0 (1 x 3 = 3) then (1 x 4 = 4) Write the answers to these sums underneath, as you would in an addition sum.
In this example, there are no numbers to carry over. If there are numbers to carry over, this can be done in the same way you would with an addition sum.
- Finally add 86 + 430.
We start by adding the numbers in the units column first (6+0 = 6)
Add the tens (8+3=11). Notice the number 11, is made up of 1 ten and 1 unit, therefore we need to carry the 1 ten over to the hundreds column and write it into our sum.
Add the hundreds (1+4=5).
x 1 2
1 8 6
+ 4 3 0
5 1 6
The answer to 43 x 12 = 516
For more step by step examples on how to work out long multiplication sums using the column method visit Teach My Kids Learning Channel.